One of the major goals this year will be the completion of entire amino acid sequences of chicken, bobwhite quail, turkey and ringnecked pheasant ovomucoids. Material is also available to start sequencing Gambel and California Valley quail, chukar, golden pheasant, chachalaca, duck and goose ovomucoids. We hope to have a supply of turtle and alligator material. The objective of this sequencing activity is twofold: (1) in distant species to determine the overall natural history of ovomucoids such as insertions and deletions and gene elongations; (2) in closely related species to determine the rate of variability of the reactive site amino acids. Methods to improve the separation of first domain of ovomucoids will be improved. A series of comparative studies on the physical chemistry of entire ovomucoid molecules and of the separated three domains will be undertaken. In one of these kinetics and thermodynamics of binding of enzymes will be compared. In another comparison will be made of the ability to undergo pH induced or thermal transitions. Further work will be carried out on the trypsin-like enzyme from Dermasterias imbricata, which rapidly and efficiently hydrolyzes reactive site peptide bonds in proteinase inhibitors. BIBLIOGRAPHIC REFERENCES: Facile Hydrolysis of the Reactive Site Peptide Bond in Pancreatic Trypsin Inhibitor (Kunitz) (PTI) by an Enzyme From the Starfish Dermasterias imbricata. D.A. Estell, K.A. Wilson and M. Laskowski, Jr. Fed. Proc. 35, 1463, (1976). Amino Acid Sequences of Third Domains of Turkey, Chicken and Japanese Quail Ovomucoids. I. Kato Fed. Proc. 35, 1621 (1976).